The present invention relates to fittings for electrodes to be used in electroarc furnaces or reducing furnaces. Such furnaces usually have a particular lid or cover and the electrodes are to be run through that cover. Concentrical to each of the electrodes are sleeves or the like cooperating with contact brackets of tubular configuration.
German patent No. 21 25 773 discloses electrode fittings of the type to which the invention pertains showing that the current feed elements in the range and vicinity of the furnace itself are protected through coaxially arranged cooling jackets. The current conductors are arranged around the electrode between the cooling jacket and that electrode. The capsulelike cooling jackets are penetrated by the magnetic field surrounding the various current feed conductors. Therefore, a high voltage is set up in these capsules. In cases the insulative - galvanic separation of the capsule from the furnace lid is actually crossed over and an electric current will flow in the capsule in the direction opposite the current flow in the current tubes. That current of the capsules induces a current in the lid or cover. Therefore the cover is inductively heated.
In summary, the known device exhibits inductive heating of the cover which is a drawback. Moreover, there may be sparks and local burning of the cover even if a high current flow only for a relatively short period of time. Another drawback is that owing to these losses there is a higher inductive nonohmic i.e. wattless resistance which in turn requires a higher power rating for the furnace transformer as well as for the conductors leading to and from the transformer.